Pressure-tight bearing.



E. G. BAILEY.

PRESSURE TIGHT BEARING.

APPLIOATION FILED APR. 30, 1913.

1,089,739, Patented Mar. 10, 191

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ut lm- 4 G Baz/Zerice ERVIN G. BAILEY, OF NEWTON HIGHLANDS,MASSACHUSETTS.

PRESSURE-TIGHT BEARING.

Specification of Letters Patent.

Patented Mar. 10, 1914.

Application filed April 30, 1913. Serial No. 764,500.

To all whom it may concern Be it known that I Envrx G. BAILEY, a citizenof the United States, residing in Newton Highlands, in the county of Middlesex and State of Massachusetts, have invented an Improvement inPressure-Tight Bearings, of which the following description, inconnection with the accompanying drawings, is a specification, likeletters on the drawings representing like parts. I

The present invention relates to a pres sure tight bearing, and isadapted for use where the fluid pressure within the casing, in the wallof which the bearing is formed, is greater or less than that of theatmos' phere, as, for example, in the case of a differential pressuregage where the pressure operated devices are inside of a fluid tightcasing, while the indicating or recording mechanism is outside, thusnecessitating the passage of a shaft or equivalent connecting devicethrough a wall of the casing. In many such instruments, the differencesof pressures encountered are very small, and it is, therefore,necessary. to eliminate, to the greatest possible extent, the oppositionto the movement of the instrument due to the friction in the bearing.The use of an ordinary stufling box, or a cup leather packing isobjectionable for this reason, the for mer because of the friction dueto the pressure needed to keep the packing tight, and the latter becauseof the fact that the pressure itself acts upon the cup leather to keepthe joint tight. Long, parallel metallic bearings have been used in somecases where the splndles are very small, but it is substantiallyimpossible to make such bearings actually pressure tight, and foreignsubstances gradually work in, thus not only producing friction, butwearing out the bearing.

The bearing embodying the present invention consists of a flat piece ofpliable material combined with the spindle which forms the male memberof the bearing, the thin piece of pliable material having a hole closelyfitting the spindle,it being possible, owing to the nature ofthematerial used, to obtain a fit which is practically pressure tightand capable of withstanding any pressure which is likel to beencountered in an instrument of t is type, and at the same time cause anegligible amount of friction, The opening for the spindle through thewall of the casing isslightly larger than the spindle itself, and oneside of the said wall at the end of the opening has a suitable surfaceagainst which the actual bearing is seated and suitably held. Anymaterial is suitable for the bearing, which is capable of yieldingslightly, and has sufficient elasticity to resist permanent displacementaround the spindle; and the term pliable has been chosen as beingcapableof use in the sense explained.

The drawing is a horizontal section, partly in elevation, of a bearingembodying the invention.

In the construction shown, the bearing is made double, the spindleextending entirely through a portion of the casing and having bearingsat opposite ends, so that the said spindle is balanced, that is,relieved from any end pressure which would result if one end of thespindle were subjected to a pressure greater than the other end.

The invention is shown as applied to a differential pressure gage, aportion of which is shown as in the form of a chamber 1, the side wallsof which are provided with bearing supports 2 which are herein shown assecured to the opposite sides of the chamber 1, bymeans of screw threads3. The spindle 4, which is actuated from the inside of the chamber bymeans of any suitable pressure receiving device through the agency ofthe arm 5, extends in opposite directions through the supportin members2, the openings in which are slightly larger than the spindle, which is,therefore, not in frictional contact with the walls of the openings.

The actual bearing for the spindle is formed in a flat piece 6 ofpliable material, such, for example, as high grade oil tan leather, thespindle tightly fitting in a hole through said flat piece, so that theflat piece constitutes the pressure-tight bearing for the spindle. Thesaid flat piece of material is held in position with the spindle in the-larger opening by means of a member 7 which is herein shown as a diskhaving an opening in line with the main opening for the spindle, thesaid disk being held aga nst the face of the bearing memberby means of ascrew threaded thimble 8 screwed on to the threaded end of the bearingmember 2. This thimble has an opening for the spindle which is largeenough to be out of contact therewith.

While it is not essential to have the bearing members at opposite sidesof the actuated arm 5, it is desirable to arrange the entire bearing inthis Way, so that no end- Wise pressure is encountered, and a certainamount of friction is thereby obviated.

Claim:-

A pressure tight bearing consisting of a spindle extending through anopening in v the Wall of a casing, said openingvbeing slightly larger indiameter'than the diameter of the spindle, combined with a flat piece ofpliable material which constitutes a bearing forthe spindle and has ahole in 'Which the said spindle fits and bears; and

means for holding said fiat piece in 'posi- 5 tion to make-a pressuretight joint, said fiat piece being held solely by confinement onopposite sides and bein free from confinement along its entire e ge. I

In testimony whereof, I have signed my 20 name to this specification inthe presence of two subscribing Witnesses.

, ERVIN G. BAILEY. Witnesses:

\J AS. J. MALoNEY, M. E. GOVENEY.

